[Functional properties of dopaminergic neurons obtained from fibroblasts of a patient with PARK2 form of Parkinson's disease].

Objective: To carry out a functional analysis of dopamine transporter (DAT) in autosomal recessive Parkinson's disease caused by mutations in the PARK2 gene.

Material And Methods: Cultures of dopaminergic neurons were obtained from fibroblasts of a patient with PARK2 form of Parkinson's disease and a healthy donor with the use of the cell reprogramming technology. DAT expression in both cell cultures was assessed at the RNA and protein levels, and DAT activity was tested with the use of the fluorescent dopamine analogue ASP+.

Results And Conclusion: In the cells with PARK2 mutations, the level of DAT expression was significantly higher than in normal neurons, but the intensity of ASP+ capture by mutant dopaminergic neurons was 25% down from normal neurons. For the study of competitive inhibition of DAT, dopamine was added to the incubation medium containing ASP+: it was shown that dopamine binding by the normal cells was almost twice as much relative to PARK2 mutant neurons. Therefore, dopaminergic neurons carrying mutations in the PARK2 gene are characterized by functional failure of dopamine transport systems. One of cell mechanisms of compensation of this defect seems to be an early increase of expression of the DAT transporter protein.